Question

The setup shown above was used for the gravimetric analysis of the empirical formula of $MgO$. In synthesizing $MgO$ from a $Mg$ strip in the crucible, which of the following is not true?

• A. The initial strip of $Mg$ should be cleaned
• B. The lid of the crucible should fit tightly to exclude oxygen
• C. The heating of the covered crucible should continue until the $Mg$ is fully reacted
• D. The crucible, lid, and the contents should be cooled to room temperature before measuring their mass
• E. When the $Mg$ appears to be fully reacted, the crucible lid should be partially removed and heating continued

Answer 1

The correct option is B The lid of the crucible should fit tightly to exclude oxygen

The setup shown above was used for the gravimetric analysis of the empirical formula of $MgO$. In synthesizing $MgO$ from a $Mg$ strip in the crucible, the following is not true.
The lid of the crucible should not fit tightly so that oxygen should come in contact with $Mg$ to synthesize $MgO$.